/*
 * Copyright (c) 2022 Huawei Device Co., Ltd.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
export function csIpvec(p, b) {
  // vars
  var k;
  var n = b.length;
  var x = []; // check permutation vector was provided, p = null denotes identity

  if (p) {
    // loop vector
    for (k = 0; k < n; k++) {
      // apply permutation
      x[p[k]] = b[k];
    }
  } else {
    // loop vector
    for (k = 0; k < n; k++) {
      // x[i] = b[i]
      x[k] = b[k];
    }
  }

  return x;
}